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Accurately lateral displacement measurement is essential for a vast of non-contact sensing technologies. Here, we introduce a high-precision lateral displacement measurement method based on differential wavefront sensing (DWS). Compared to the conventional differential power sensing (DPS) method, the DWS method based on phase readout has the potential to achieve a higher resolution. The beam lateral displacement can be obtained by the curvature distribution of the wavefront on the surface of the detector. According to the theoretical model of the DWS method, the sensitivity of the lateral displacement can be greatly improved by increasing the wavefront curvature of the measured laser beam by means of lenses. An optical system for measuring the lateral displacement of the laser beam is built and calibrated by a high-precision hexapod. The experimental results show that the DWS-based lateral displacement measurement achieves a resolution of 40â pm/Hz1/2 (at 1-10â Hz) with a linear range of about 40â µm, which is consistent with the theoretical model. This technique can be applied to high-precision multi-degree-of-freedom interferometers.
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Velocity and displacement measurements play an important role not only in the process of industrial production and metrology on the ground but also in satellite gravity measurement in space. A high-precision all-fiber heterodyne velocity and displacement interferometer based on digital phase-locked loop (DPLL) Doppler tracking is proposed in this paper. The target velocity is measured by tracking the heterodyne frequency changes of the beat-note signal, and the displacement is obtained by the integrated phase of the Doppler frequency change. A dual-signal differential optical-path scheme combined with DPLL signal tracking technology enables high-precision and high-linearity measurement of velocity and displacement simultaneously. For integration and compactness, the interferometer uses all-fiber optics that are packaged in a small box with dimensions of 150×150×70m m 3, except for an externally fiber-connected collimator as the sensor head. The experimental results show a velocity sensitivity below 30p m/s/H z 1/2 in the 0.03-2 Hz band and a displacement sensitivity below 10p m/H z 1/2 above 0.4 Hz.
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OBJECTIVE: This study explored the feasibility of mesoplasty with end-to-side anastomosis in the treatment of different apple-peel mesenteric defects with high jejunal atresia. METHODS: A retrospective analysis was performed on 42 premature infants admitted to the hospital between 2014 and 2021. Prenatal ultrasound scans revealed bowel dilatation. The patients experienced vomiting after birth and produced white or no meconium. Plain radiography showed double or triple bubble signs and the patients underwent emergency laparotomy. High jejunal atresia with different apple-peel atresia appearance was discovered intraoperatively, involving mobilization of the ileocecal region. Patients received end-to-side anastomosis between the enlarged blind pouch and atretic bowel, as well as mesoplasty. A jejunal feeding tube was placed trans-nasally. Patients were discharged after achieving full enteral feeding. We also reviewed the literature on the subject. RESULTS: Three patients died and 39 survived. The discharged patients were followed up for 12 months, and none showed post-operative complications such as intestinal obstruction, malnutrition, or chronic diarrhea. All surviving patients reached the expected height and weight for children of the same age. CONCLUSION: For cases of high jejunal atresia with apple-peel intestinal atresia, mesoplasty may be a good option to avoid postoperative volvulus.
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Atresia Intestinal , Anastomose Cirúrgica , Criança , Feminino , Humanos , Lactente , Atresia Intestinal/complicações , Atresia Intestinal/diagnóstico , Atresia Intestinal/cirurgia , Jejuno/cirurgia , Mesentério/cirurgia , Gravidez , Estudos RetrospectivosRESUMO
PURPOSE: We measured the expression of the histone demethylase lysine-specific demethylase 5B (KDM5B) in the bowels of patients with Hirschsprung's disease (HSCR) and investigated the molecular mechanism by which KDM5B promotes the migration of neuronal PC12 cells. METHODS: KDM5B expression was detected in the ganglionic and aganglionic colon of patients with HSCR (n = 10) and controls (n = 10). The expression and localization of KDM5B were assessed using immunohistochemical and immunofluorescence staining. Real-time PCR and Western blotting were performed to quantify KDM5B expression. The migration was determined using Transwell and wound-healing assays. G-LISA, GTPase pulldown and luciferase-based reporter gene assays were performed to evaluate the key components of Wnt/planar cell polarity (PCP) signaling in vitro. RESULTS: Our current study showed that KDM5B colocalized with neurons. KDM5B expression was reduced in HSCR specimens, while the aganglionic segments showed the greatest reduction. KDM5B knockdown inhibited the migration of PC12 cells. Moreover, inhibition of KDM5B decreased the expression of key genes in the Wnt/PCP pathway, and its inhibitory effect on PC12 cell migration was reversed by Wnt5a treatment. CONCLUSIONS: KDM5B promotes neuronal migration via the Wnt/PCP pathway. A potential role for KDM5B in altered enteric nervous system development in HSCR warrants further investigation.
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Doença de Hirschsprung , Movimento Celular , Colo , Gânglios , Doença de Hirschsprung/genética , Humanos , Intestinos , Histona Desmetilases com o Domínio Jumonji , Proteínas Nucleares , Proteínas RepressorasRESUMO
An in-plane displacement sensor based on an asymmetric extrinsic fiber Fabry-Perot interferometer (EFPI) is proposed and demonstrated. The asymmetric EFPI composed of a step-shaped external reflector and a cleaved fiber end face can be equivalent to two parallel FPIs with slightly different cavity lengths. By calculating the peak intensity difference of the two FPIs, the in-plane displacement can be demodulated with enhanced sensitivity and suppressed common mode noise. Both theoretical analyses and experimental results show that the sensitivity and the linear range of the in-plane displacement sensor are dependent on the cavity length. A displacement resolution of 5 nm and a linear range of ±7µm under the cavity length of 250 µm are achieved in the experiment. The proposed in-plane displacement sensor with a nanometric resolution and compact size can be widely used in the fields of metrology, accelerometers, and semiconductor manufacture.
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Sparse signal processing has already been introduced to synthetic aperture radar (SAR), which shows potential in improving imaging performance based on raw data or a complex image. In this paper, the relationship between a raw data-based sparse SAR imaging method (RD-SIM) and a complex image-based sparse SAR imaging method (CI-SIM) is compared and analyzed in detail, which is important to select appropriate algorithms in different cases. It is found that they are equivalent when the raw data is fully sampled. Both of them can effectively suppress noise and sidelobes, and hence improve the image performance compared with a matched filtering (MF) method. In addition, the target-to-background ratio (TBR) or azimuth ambiguity-to-signal ratio (AASR) performance indicators of RD-SIM are superior to those of CI-SIM in down-sampling data-based imaging, nonuniform displace phase center sampling, and sparse SAR imaging model-based azimuth ambiguity suppression.
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Quantum spin Hall (QSH) effect is an intriguing phenomenon arising from the helical edge states in two-dimensional topological insulators. We use molecular beam epitaxy (MBE) to prepare FeSe films with atomically sharp nematic domain boundaries, where tensile strains, nematicity suppression, and topological band inversion are simultaneously achieved. Using scanning tunneling microscopy (STM), we observe edge states at the Fermi level that spatially distribute as two distinct strips in the vicinity of the domain boundaries. At the end point of the boundaries, a bound state at the Fermi level is further observed. The topological origin of the edge states is supported by density functional theory calculations. Our findings not only demonstrate a candidate for QSH states but also provide a new pathway to realize topological superconductivity in a single-component film.
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Vectorial nature of dissipative solitons (DSs) with high repetition rate is studied for the first time in a normal-dispersion fiber laser. Despite the fact that the formed DSs are strongly chirped and the repetition rate is greater than 100 MHz, polarization locked and polarization rotating group velocity locked vector DSs can be formed under 129.3 MHz fundamental mode-locking and 258.6 MHz harmonic mode-locking of the fiber laser, respectively. The two orthogonally polarized components of these vector DSs possess distinctly different central wavelengths and travel together at the same group velocity in the laser cavity, resulting in a gradual spectral edge and small steps on the optical spectrum, which can be considered as an auxiliary indicator of the group velocity locked vector DSs. Moreover, numerical simulations well confirm the experimental observations and further reveal the impact of the net cavity birefringence on the properties of the formed vector DSs.
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In this paper, we investigate and experimentally demonstrate the influences of distance between the silica core and the glycerin core of a selectively glycerin-infiltrated photonic crystal fiber (PCF) on the mode characteristics, as well as the temperature sensitivity. By comparing the simulation and experiment results of three single-void glycerin-infiltrated PCFs with the glycerin core being one period, two periods and three periods away from the silica core respectively, it reveals that the smaller distance between the silica core and the glycerin core does not affect the modes indices, but increases the intensities of modes in the glycerin core and thus enhances the temperature sensitivity. Consequently, the temperature sensitivity can be controlled and tuned by appropriately designing the structure parameters of glycerin-infiltrated PCF. Besides, the highest temperature sensitivity up to -3.06nm/°C is obtained in the experiment as the glycerin core is nearest to the silica core. This work provides insights into the design and optimization of the liquid-infiltrated PCF for sensing applications.
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The intracellular parasite Toxoplasma gondii is a major cause of abortion and neonatal loss in livestock, and can cause severe illness to human with weakened immune system. The heavy incidence and severe consequence indicate the development of vaccines against T. gondii is required. In this study, DNA vaccines encoding GRA1 and MIC3 antigens were developed. The parasite-specific immune responses and protection efficiency against toxoplasmosis by these DNA vaccines were evaluated in BALB/c mice. The results demonstrated that the IgG antibody production was significantly increased in multi-antigenic vaccine encoding GRA1 and MIC3 immunized group, as well as the IFN-γ level, when compared with single-gene vaccines and controls groups (p < 0.05). Two weeks after the final vaccination, the mice were challenged with either 1 × 10(4) or 1 × 10(2) RH strain tachyzoites, and the mortality and parasite reduction were observed. The multi-antigenic vaccine encoding GRA1 and MIC3 lead to the longest survival time as well as the less parasite-loads in brain and liver of immunized mice (p < 0.01). The present study indicates that the GRA1 and MIC3 showed the potential as target for vaccine investigation against toxoplasmosis. And the immune efficacy induced by multi-antigenic vaccine encoding GRA1 and MIC3 was better than that induced by single-antigenic vaccines alone.
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Antígenos de Protozoários/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias , Toxoplasma/imunologia , Toxoplasmose Animal/prevenção & controle , Vacinas de DNA , Animais , Anticorpos Antiprotozoários/biossíntese , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/genética , Antígenos de Protozoários/metabolismo , Encéfalo/parasitologia , Citocinas/biossíntese , Feminino , Imunofluorescência , Expressão Gênica , Células HEK293 , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Vacinas Protozoárias/imunologia , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , Baço/citologia , Baço/imunologia , Toxoplasmose Animal/imunologia , Vacinas de DNA/imunologiaRESUMO
An optical chaos and hybrid wavelength division multiplexing/time division multiplexing (WDM/TDM) based large capacity quasi-distributed sensing network with real-time fiber fault monitoring is proposed. Chirped fiber Bragg grating (CFBG) intensity demodulation is adopted to improve the dynamic range of the measurements. Compared with the traditional sensing interrogation methods in time, radio frequency and optical wavelength domains, the measurand sensing and the precise locating of the proposed sensing network can be simultaneously interrogated by the relative amplitude change (RAC) and the time delay of the correlation peak in the cross-correlation spectrum. Assisted with the WDM/TDM technology, hundreds of sensing units could be potentially multiplexed in the multiple sensing fiber lines. Based on the proof-of-concept experiment for axial strain measurement with three sensing fiber lines, the strain sensitivity up to 0.14% RAC/µÎµ and the precise locating of the sensors are achieved. Significantly, real-time fiber fault monitoring in the three sensing fiber lines is also implemented with a spatial resolution of 2.8 cm.
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We propose and experimentally demonstrate a refractive index (RI) sensor based on cascaded microfiber knot resonators (CMKRs) with Vernier effect. Deriving from high proportional evanescent field of microfiber and spectrum magnification function of Vernier effect, the RI sensor shows high sensitivity as well as high detection resolution. By using the method named "Drawing-Knotting-Assembling (DKA)", a compact CMKRs is fabricated for experimental demonstration. With the assistance of Lorentz fitting algorithm on the transmission spectrum, sensitivity of 6523nm/RIU and detection resolution up to 1.533 × 10(-7)RIU are obtained in the experiment which show good agreement with the numerical simulation. The proposed all-fiber RI sensor with high sensitivity, compact size and low cost can be widely used for chemical and biological detection, as well as the electronic/magnetic field measurement.
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Towards the next generation optical access network supporting large capacity data transmission to enormous number of users covering a wider area, we proposed a hybrid wavelength-space division multiplexing (WSDM) optical access network architecture utilizing multicore fibers with advanced modulation formats. As a proof of concept, we experimentally demonstrated a WSDM optical access network with duplex transmission using our developed and fabricated multicore (7-core) fibers with 58.7km distance. As a cost-effective modulation scheme for access network, the optical OFDM-QPSK signal has been intensity modulated on the downstream transmission in the optical line terminal (OLT) and it was directly detected in the optical network unit (ONU) after MCF transmission. 10 wavelengths with 25GHz channel spacing from an optical comb generator are employed and each wavelength is loaded with 5Gb/s OFDM-QPSK signal. After amplification, power splitting, and fan-in multiplexer, 10-wavelength downstream signal was injected into six outer layer cores simultaneously and the aggregation downstream capacity reaches 300 Gb/s. -16 dBm sensitivity has been achieved for 3.8 × 10-3 bit error ratio (BER) with 7% Forward Error Correction (FEC) limit for all wavelengths in every core. Upstream signal from ONU side has also been generated and the bidirectional transmission in the same core causes negligible performance degradation to the downstream signal. As a universal platform for wired/wireless data access, our proposed architecture provides additional dimension for high speed mobile signal transmission and we hence demonstrated an upstream delivery of 20Gb/s per wavelength with QPSK modulation formats using the inner core of MCF emulating a mobile backhaul service. The IQ modulated data was coherently detected in the OLT side. -19 dBm sensitivity has been achieved under the FEC limit and more than 18 dB power budget is guaranteed.
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BACKGROUND: Enterocolitis (EC) is the most common and serious postoperative complication of Hirschsprung's disease (HD). Probiotics potentially play a protective role in maintaining intestinal mucosal integrity. Based on the beneficial effects of probiotics, we hypothesized that oral probiotics could decrease the incidence and severity of Hirschsprung's disease-associated enterocolitis (HAEC). METHODS: We conducted a prospective, multicenter, randomized, and controlled trial to assess whether oral probiotics could decrease the incidence and severity of HAEC. HD patients were randomly assigned into the control group and probiotic-treated group. All children in probiotic-treated group were fed with probiotics per day for 4 weeks. In next 3 months, the incidence and severity of HAEC were analyzed. The peripheral blood T lymphocyte subsets and cytokines, including TNF-α, IFN-γ, IL-6, and IL-10, were analyzed by flow cytometry and enzyme immunoassay (EIA). RESULTS: Compared with the control group, the incidence of HAEC in the probiotic-treated group was significantly diminished. The severity of EC was also remarkably decreased. Furthermore, probiotics balanced T lymphocyte subsets. Moreover, pro-inflammatory cytokines TNF-α, IFN-γ, and IL-6 were significantly decreased and anti-inflammatory cytokine IL-10 was notably increased in probiotic-treated group. CONCLUSIONS: Probiotics not only significantly diminished the incidence but also decreased the severity of HAEC. Moreover, our study revealed that probiotics decreased pro-inflammatory cytokine and increased anti-inflammatory cytokine and furthermore balanced T lymphocytes (registered with ClinicalTrials.gov, NCT number: NCT01934959).
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Enterocolite/prevenção & controle , Doença de Hirschsprung/complicações , Probióticos/uso terapêutico , Administração Oral , Adolescente , Antígenos CD4/sangue , Antígenos CD8/sangue , Criança , Pré-Escolar , Citocinas/sangue , Enterocolite/sangue , Enterocolite/etiologia , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Índice de Gravidade de DoençaRESUMO
Design space approach is applied in this study to enhance the robustness of first ethanol precipitation process of Codonopsis Radix (Dangshen) by optimizing parameters. Total flavonoid recovery, dry matter removal, and pigment removal were defined as the process critical quality attributes (CQAs). Plackett-Burman designed experiments were carried out to find the critical process parameters (CPPs). Dry matter content of concentrated extract (DMCE), mass ratio of ethanol to concentrated extract (E/C ratio) and concentration of ethanol (CEA) were identified as the CPPs. Box-Behnken designed experiments were performed to establish the quantitative models between CPPs and CQAs. Probability based design space was obtained and verified using Monte-Carlo simulation method. According to the verification results, the robustness of first ethanol precipitation process of Dangshen can be guaranteed by operating within the design space parameters. Recommended normal operation space are as follows: dry matter content of concentrated extract of 45.0% - 48.0%, E/C ratio of 2.48-2.80 g x g(-1), and the concentration of ethanol of 92.0% - 92.7%.
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Química Farmacêutica/métodos , Codonopsis/química , Medicamentos de Ervas Chinesas/química , Precipitação Química , Medicamentos de Ervas Chinesas/isolamento & purificaçãoRESUMO
A multimode microfiber (MMMF)-based dual Mach-Zehnder interferometer (MZI) is proposed and demonstrated for simultaneous measurement of refractive index (RI) and temperature. By inserting a section of MMMF supporting a few modes in the sensing arm of the MZI setup, an inline interference between the fundamental mode and the high-order mode of MMMF, as well as the interference between the high-order mode of MMMF and the reference arm, i.e., the dual MZI, is realized. Due to different interference mechanisms, the former interferometer achieves RI sensitivity of 2576.584 nm/RIU and temperature sensitivity of -0.193 nm/°C, while the latter one achieves RI sensitivity of 1001.864 nm/RIU and temperature sensitivity of 0.239 nm/°C, demonstrating the ability to attain highly accurate multiparameter measurements.
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Interferometria/métodos , Refratometria/métodos , Desenho de Equipamento , Tecnologia de Fibra Óptica , Interferometria/instrumentação , Fibras Ópticas , Fenômenos Ópticos , Refratometria/instrumentação , TemperaturaRESUMO
Three-dimensional donor-acceptor (D-A) type conjugated porous polymers (CPPs) was designed and synthesized via imine condensation of copper tetraaminoporphyrin (CuTAPP) as donor and 1,3,5-tris-(4-formyl phenyl) triazine (TFPT) as acceptor, named as CuPT-CPP. The CuPT-CPP possesses a high specific surface area (73.7 m2/g) and excellent photophysical properties. The simultaneous introduction of the organometallic molecules and D-A structures in CuPT-CPP could be broadened the visible-light response range (400-800 nm) and facilitated efficient photogenerated carrier separation and transportation. As heterogeneous photocatalysts, CuPT-CPP has excellent photocatalytic performances under visible light irradiation, leading to excellent model pollutant rhodamine B degradation efficiency up to about 100% in 3 h, it has superb stability and reusability during the photocatalytic processes, and CuPT-CPP also exhibited broad substrate adaptability, which could photocatalytic degradation of methylene blue (MB), methyl orange (MO), and tetracycline hydrochloride (TC). This work indicates that three-dimensional D-A type porphyrin- and triazine-based CuPT-CPP has great potential in the practical application of photocatalysis.
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Poluentes Ambientais , Porfirinas , Água , Fotólise , Porosidade , Metais , PolímerosRESUMO
With the increasing application of artificial intelligence (AI) in medicine and healthcare, AI technologies have the potential to improve the diagnosis, treatment, and prognosis of rare diseases. Presently, existing research predominantly focuses on the areas of diagnosis and prognosis, with relatively fewer studies dedicated to the domain of treatment. The purpose of this review is to systematically analyze the existing literature on the application of AI in the treatment of rare diseases. We searched three databases for related studies, and established criteria for the selection of retrieved articles. From the 407 unique articles identified across the three databases, 13 articles from 8 countries were selected, which investigated 10 different rare diseases. The most frequently studied rare disease group was rare neurologic diseases (n = 5/13, 38.46%). Among the four identified therapeutic domains, 7 articles (53.85%) focused on drug research, with 5 specifically focused on drug discovery (drug repurposing, the discovery of drug targets and small-molecule inhibitors), 1 on pre-clinical studies (drug interactions), and 1 on clinical studies (information strength assessment of clinical parameters). Across the selected 13 articles, we identified total 32 different algorithms, with random forest (RF) being the most commonly used (n = 4/32, 12.50%). The predominant purpose of AI in the treatment of rare diseases in these articles was to enhance the performance of analytical tasks (53.33%). The most common data source was database data (35.29%), with 5 of these studies being in the field of drug research, utilizing classic databases such as RCSB, PDB and NCBI. Additionally, 47.37% of the articles highlighted the existing challenge of data scarcity or small sample sizes.
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Two novel flavonoid glycosides, 6"'-dihydrophaseoylspinosin (1) and 6â³,6"'-diferuloylspinosin (2), were isolated from the MeOH extract of Semen Ziziphi Spinosae, together with six known flavonoids, isovitexin-2â³-O-ß-(6-O-E-feruloyl)glucopyranoside (3), spinosin (4), isospinosin (5), 6"'-feruloylspinosin (6), swertisin (7), and isovitexin-2â³-O-ß-d-glucopyranoside (8). The structures of 1 and 2 were elucidated by spectroscopic methods including UV, IR, ESI-TOF-MS, 1D NMR, and 2D NMR experiments.
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Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Apigenina/química , Apigenina/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
A novel spinosin derivative, 6â´-(4â´'-O-ß-D-glucopyranosyl)-vanilloyl spinosin (1) was isolated from the methanol extract of Semen Ziziphi Spinosae, together with five known flavonoids, swertish, spinosin, 6â´-feruloylspinosin, isospinosin and kaempferol 3-O-α-L-rhamnopyranosyl-(1 â 2)-O-[O-α-L-rhamnopyranosyl-(1 â 6)]-ß-D-glucopyranoside, and two alkanoids, zizyphusine and 6-(2',3'-dihydroxyl-4'-hydroxymethyl-tetrahydro-furan-1'-yl)-cyclopentene[c]pyrrole-1,3-diol. The structure of compound 1 was elucidated by spectroscopic methods including UV, IR, ESI-TOF-MS, 1D, and 2D NMR techniques.